RE: EXT :Stupid software requirements - need your examples
Date: Thu, 17 Feb 2011 15:55:40 +0000
Message-ID: <8AE45871F749FC4CBBE053CF2F8A493C08C804_at_XMBVAG74.northgrum.com>
Here is one that I inherited. The environment was a COTS CRM application with significant customizations. Management reports for things like SLA's were run off of a data warehouse. A consulting company had been initially hired to design the data warehouse and the ETL process based on a requirement to move data to the warehouse once a day. By the time I assumed DBA responsibilities the whole system had been running in production for about four years. Shortly after I arrived management decided that since the whole environment was mature they no longer needed the guy who supported Informatica, the package that was running the ETL's.
My manager asked me to look into what we could do to make the ETL's run faster, like maybe reorganize some tables. Investigating, I found that they were running a full ETL (the one that the consultant had designed to be run once a day) every hour and the ETL's were taking 65 to 75 minutes. At this point I knew nothing about the design history of the project so I did not know that the ETL's were originally designed to be run once a day. In a conversation with Informatica the tech support the guy mentioned something about incremental versus full ETL's and a light bulb came on. I started asking questions and learned that the customer had complained that their updates were not showing up in the reports so they changed from running the full ETL once a day to running four times a day. Apparently, that was not enough, so they switched to running them hourly.
I did a bit on analysis and found that the longest step in the ETL process was taking 14 to 20 minutes each time it ran. A 10046 trace showed that this step updating every row of a 1.1 million row table (plus adding a few new rows) every hour. Fewer than 1% of the rows in that table, however, were actually changing.
- Peter Schauss
-----Original Message-----
From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Gints Plivna
Sent: Thursday, February 17, 2011 9:17 AM
To: Oracle L
Subject: EXT :Stupid software requirements - need your examples
Hello!
I'm quite sure most of you at least once have been in a situation when you HAD TO implement a requirement, which is stupid, results in slow performance and in principle cannot be optimized. And you either silently or loudly blamed the person who could imagine something like that :)
So (as I'm actually mostly system analyst) I'm seeking examples for a small presentation to highlight such cases for my colleagues to avoid them. I know quite many developers blame requirements gatherers and system analysts for these requirements and they are right, because such requirements should not be accepted or at least customer has to be informed about the consequences.
-- http://www.freelists.org/webpage/oracle-lReceived on Thu Feb 17 2011 - 09:55:40 CST